First Day of Seasons 2017 and 2018 | Fall Equinox, Winter Solstice, Spring Equinox, Summer Solstice | The Old Farmer's Almanac December 21, 5:23 P.M. EST Why Do the Seasons Change? The four seasons are determined by shifting sunlight (not heat!)—which is determined by how our planet orbits the Sun and the tilt of its axis. Photo Credit: NASA On the vernal equinox , day and night are each approximately 12 hours long (with the actual time of equal day and night, in the Northern Hemisphere, occurring a few days before the vernal equinox). The Sun crosses the celestial equator going northward; it rises exactly due east and sets exactly due west. See our First Day of Spring page . On the summer solstice , we enjoy the most daylight of the calendar year. The Sun reaches its most northern point in the sky at local noon. After this date, the days start getting “shorter,” i.e., the length of daylight starts to decrease. See our First Day of Summer page .

On the autumnal equinox , day and night are each about 12 hours long (with the actual time of equal day and night, in the Northern Hemisphere, occurring a few days after the autumnal equinox). The Sun crosses the celestial equator going southward; it rises exactly due east and sets exactly due west. See our First Day of Fall page . The winter solstice is the “shortest day” of the year, meaning the least amount of sunlight. The Sun reaches its most southern point in the sky at local noon. After this date, the days start getting “longer,” i.e., the amount of daylight begins to increase. See our First Day of Winter page . First Day of Fall 2016 Autumnal Equinox Dates Times Photos | The Old Farmer's Almanac Average: 3.5 (747 votes) Autumn starts again with the equinox on September 22. Welcome in the fall season! Specifically, the Northern Hemisphere marks the autumnal equinox on Friday, September 22, 2017, at exactly 4:02 P.M. EDT.

Watch the video below for a re-play or our live show, “Celebrating the September Equinox.” We share observatory views, courtesy of Slooh , plus interesting equinox facts and folklore. What is the Autumnal Equinox? The September equinox is the astronomical start of fall in the Northern Hemisphere and spring in the Southern Hemisphere. The word equinox means “equal night”; night and day are about the same length of time. During the equinox, the Sun crosses what we call the “celestial equator” (just imagine the line that marks the equator on Earth extending up into the sky) from north to south. At this point, the amount of nighttime and daytime are roughly equal to each other. Another definition of fall is nights of below-freezing temperatures combined with days of temperatures below 70 degrees Fahrenheit. From here on out, the temperatures begin to drop and the days start to get shorter than the nights (i.e., hours of daylight decline ). It is the summer’s great last heat, It is the fall’s first chill: They meet. –Sarah Morgan Bryan Piatt What’s in store for your winter weather? Order you copy of The Old Farmer’s Almanac !

Equal Days and Nights Nights and days actually aren’t perfectly equal on the equinox, as in 12 hours of daylight and 12 hours of nighttime. The split may be off by a few minutes. Why does this happen? It depends where you live. On the equinoxes, the very center of the Sun sets just 12 hours after it rises. But the day begins when the upper edge of the Sun reaches the horizon (which happens a bit before the center rises), and it doesn’t end until the entire Sun has set. Not only that, but the Sun is actually visible when it is below the horizon, as Earth’s atmosphere refracts the Sun’s rays and bends them in an arc over the horizon. According to our former astronomer, George Greenstein, “If the Sun were to shrink to a starlike point and we lived in a world without air, the spring and fall equinoxes would truly have ‘equal nights.’” What Falling Leaves Indicate There’s an old weather proverb that states, “If autumn leaves are slow to fall, prepare for a cold winter.” This means that leaves tht hang onto the tree indicate a colder winter to come. Or, perhaps you just haven’t had enough windy days!

But look on the bright side—you get to look at the beautiful autumn foliage for a little bit longer. Learn why autumn leaves change color . Signs of Fall In many regions of North America, the landscape silently explodes with vibrant colors of red, yellow, and orange. The leaves begin to drop off the trees, providing endless hours of jumping into leaf piles for kids and raking them back up for parents! Baseball season hits the homestretch, while football season is just warming up. Temperatures begin to drop, nights begin to get longer, and all the woodland critters are storing up for the long haul of winter. How do you know that fall is coming? Share your comment below! Autumn Folklore and Verse Autumn days come quickly, like the running of a hound on the moor. –Irish proverb Trees snapping and cracking in the autumn indicate dry weather. If, in the fall of the leaves in October, many of them wither on the boughs and hang there, it betokens a frosty winter and much snow. Spring rain damps; Autumn rain soaks. Of autumn’s wine, now drink your fill; the frost’s on the pumpkin, and snow’s on the hill.

–The Old Farmer’s Almanac, 1993 Autumn has caught us in our summer wear. –Philip Larkin, British poet (1922–86) Vernal Equinox Marks First Day of Spring Today Vernal Equinox Marks First Day of Spring Today Geoff Gaherty Pin it Share The vernal equinox, which marks the first day of the northern Spring season, occurs at 7:02 a.m. EDT on March 20, 2013. More The vernal equinox, which occurs at 7:02 a.m. EDT today (March 20), is probably the most important astronomical event of the year. Although popularly described as " the first day of spring " in the Northern Hemisphere, the annual event is actually much more important than that. More than any other event, it marks the beginning of the astronomical year. For something so important in astronomy, it’s surprising that it is something that you cannot observe in any way in the night sky . That’s because it involves the sun, which floods the sky with light and makes it impossible to see what is actually happening.

Modern planetarium software enables us to dim the sun, so that we can see what it is doing in the context of the planets around it and the stars behind it. [ 6 Signs that Spring Has Sprung ] In the graphic accompanying this story, the celestial equator (located directly above the Earth’s equator) is marked by a red line. Crossing it at an angle is a green line which marks the ecliptic, the path which the sun follows in front of the background stars. This is tilted at an angle because the Earth’s axis of rotation is at an angle, 23.5 degrees. Notice the months marked along the ecliptic: these indicate the sun's position. February is below and to the right; April is above and to the left. The sun sits on March 20 right in the center. So the sun appears to be moving from right to left across the chart. In reality, of course, it is the Earth that is moving, and not the sun, but from our viewpoint on Earth it seems just the opposite. What happens on March 20 is that the sun moves from south of the celestial equator to north of the equator.

The days, which have been getting longer since winter solstice on Dec. 21, now equal the nights in length, which is why this is called the "equinox" — Latin for "equal nights." From now until the summer solstice on June 21, the days will gradually get longer because the sun will be higher in the sky, giving more hours of daylight. More hours of sun means more warming by the sun, so the days will also get warmer. Also the sun's rays will be striking the northern hemisphere from a more acute angle, so that the same amount of solar radiation is concentrated in a smaller area, amplifying the heating factor. The graphic shows the constellations in their modern positions. The point at which the equator and the ecliptic cross, traditionally called "the first point in Aries," actually lies today in the constellation Pisces. Aries, where it used to lie, is now up in the upper left corner of the chart.

Similarly, the summer equinox now puts the sun in Sagittarius, off the chart to the lower right, even though it gives its name to the "tropic of Capricorn." One of the differences between astronomy and astrology is that astronomy uses the current positions of the sun and planets in the sky, while astrology uses historical positions which have been out-of-date for thousands of years. Because the sky has been darkened by the software, we can see how several planets are gathered on the far side (behind) the sun: Uranus, Mars, and Venus. Above the sun and to its left (east) is Comet Pan-STARRS . Below and to the left is the distant dwarf planet Eris, hovering in the far reaches of the solar system. How did ancient peoples observe and measure the date of the vernal equinox, if it is blocked by the sunlit sky? They discovered clever ways of marking the rising and setting points of the sun. In some cases they built monuments to refine these measurements. Stonehenge , in southern England, is one of the most spectacular examples of these equinox calendars. What happens in the Southern Hemisphere when the sun crosses the equator into the northern sky?

There the days grow shorter and the temperature drops. Today is in fact the southern autumnal equinox, heading towards winter. The seasons in the Southern Hemisphere are a mirror image of the ones in the north. It’s quite clear why the vernal equinox has become known as the first day of spring, and why its equivalent when the sun moves south again on Sept. 22, the autumnal equinox, is the first day of fall. What’s more puzzling is why the "in between" markers are known as "midwinter" and "midsummer" when we all know that they both occur rather early in their named seasons. This happens because the Earth's weather seasons actually lag a month or two behind the astronomical markers. Anyway, enjoy the longer days and warmer weather. This article was provided to SPACE.com by Starry Night Education , the leader in space science curriculum solutions. Follow Starry Night on Twitter @StarryNightEdu . Original article on SPACE.com . First Day of Spring Marked With Sun Daggers, Light Snakes First Day of Spring Marked With Sun Daggers, Light Snakes Across the Americas, ancient cultures marked the equinox in stunning ways—some of which are still alive and thriving.

View Images At equinox, a blazing serpent of light (left) appears to slither down the side of El Castillo pyramid, at the Mayan site of Chichén Itzá. Photograph by Israel Leal, AP Twice each year, as the sun marches across the sky, its center crosses Earth’s equator. This celestial alignment results in the equinox—a day with light and dark of ( nearly ) equal length, with the sun rising precisely in the east and setting precisely in the west. This year, the two equinoxes will occur on March 20 and September 22. For most people, the equinox simply heralds a changing of the seasons. In March, the vernal equinox signals the beginning of spring in the Northern Hemisphere and autumn in the southern, and the reverse happens during the autumnal equinox. But for many ancient cultures across the Americas, equinoxes were something more: a time for celebration, sacrifice, and migration. You Might Also Like The Autumn Equinox is Here! Wait, What's the Autumn Equinox? For millennia, observing the sun’s shifting path was both essential for survival and hard to ignore.

Our star’s celestial wanderings foretold the onset of the growth and harvest seasons and warned of impending winter, so it’s not unusual to find a variety of solar calendars among the artifacts of vanished civilizations. Other cultures are keeping their traditions alive, and still performing ceremonies timed to the equinox. Ancient Calendars Many people have heard of the Mayan calendar, but others are lesser known. In the Peruvian desert north of Lima, at a site called Chankillo , an enormous astronomical observatory sits atop a ridge. Dating back to at least 500 B.C., the installation is a complex array of 13 towers, fashioned in a north-south line resembling a spine. View Images Atop Fajada Butte in New Mexico, ancient spirals etched into rock are sliced through by daggers of light at solstice and equinox. Photograph by Scott S. Warren, National Geographic Creative As the sun moves through its yearly paces, it rises and sets between the towers at predictable times, appearing to the left of the first tower at the summer solstice, in the center at equinox, and to the right of the last tower at winter solstice.

“The extreme end towers are very clearly marking the solstices, though the argument for the equinox is more indirect,” notes archaeologist Iván Ghezzi of Peru’s Institute for Archaeological Research, who described the site’s solar connection in 2007 . The identity of the observatory’s builders is still unknown, but like many ancient cultures in the Americas, they appeared to worship the sun. “Chankillo is much more than merely an astronomical observatory,” Ghezzi says. “It’s a site that was a large ceremonial center.” Chankillo, though still fundamentally enigmatic, is one of many examples of structures built to align with the equinox, such as a Stonehenge-like circle of wooden poles, or Woodhenge , at a prehistoric site called Cahokia in Southern Illinois, and the earthen lodges oriented toward astronomical features built by the Skidi Pawnee. Light, Shadow, and Sacrifice But sometimes, simply marking astronomical alignments isn’t enough; another ancient method of tracing the sun’s meanderings through the sky involves using light and shadow to paint particular images. Here, the sunlight itself does the work, inscribing illuminated shapes or casting shadows.

One example of this is at Chichén Itzá , where the Mayans crafted a sculpture that transforms itself into a blazing serpent at equinox, representing their deity Kukulcan. Another image in light was discovered in 1977, when rock artist Anna Sofaer was exploring the petroglyphs of the American southwest. There, at the top of New Mexico’s Fajada Butte, Sofaer found what’s known as the Sun Dagger, a calendrical marking created from two spirals etched into the rock. During summer solstice and equinox, the spirals are sliced by a dagger of light as the sun shines through slabs of rock; at winter solstice, two daggers appear on either side of the spiral—or did. The rock slabs have shifted and the images no longer appear . Equinoxes Just twice a year, day and night fall into perfect balance. Some claim that astronomical phenomenon, called equinox, inspires ancient structures to reveal hidden secrets. The site is in Chaco Canyon, where an ancient civilization thrived for millennia before mysteriously abandoning their city. Further evidence, in the form of interred bird bones, suggests that the Chaco Canyon inhabitants marked the equinox by sacrificing scarlet macaws.

They’re not alone: The practice was apparently quite common among the Puebloans of the Southwest and Northern Mexico. “In many of areas of the ancient New World, scarlet macaws were symbolically associated with the sun and with fire, probably because of their red and yellow feathers,” says UCSD anthropologist Andrew Somerville , who has worked extensively at a site called Paquime in northern Mexico. “By sacrificing a symbol of the sun on this solar holiday, one was perhaps ritually ending the dry season and hastening the arrival of the spring and summer rains.” Living Traditions Some Native American equinox traditions are still alive. For the native Lakota of the U.S. midwest, the vernal equinox not only kicked off a seasonal migration in the Black Hills of South Dakota, but a series of ceremonies meant to welcome life on Earth and send the souls of the deceased to briefly rest in the core of the Milky Way. View Images At Chankillo, in Peru, a vanished civilization crafted not only a grand solar observatory, but also buildings that archaeologists suspect are ceremonial centers for the ancient sun-worshippers.

Photograph by Werner Forman, Universal Images Group/Getty “Our people, for all these years, have done that,” says Victor Douville, who teaches the ethnoastronomy course at Sinte Gleska University on the Rosebud Reservation in South Dakota. Millennia ago, Douville says, the Lakota noticed that every spring, the sun rises in the constellation known as the Dried Willow. “Those stars look like nubs on the branch, and the branch represents the red willow,” Douville says. The inner bark of that red willow is the main ingredient used to make tobacco for the equinoctial Sacred Pipe ceremony, which is meant to rekindle the sacred fire of life on Earth. The ceremony is the first in a series of four that culminates with the Sun Dance on the summer solstice. Next week, he says, the Lakota will perform the Pipe ceremony; the other three will unfold as the sun travels through three additional constellations. For a long time, scholars thought only settled, agricultural societies marked the movements of the heavens. Yet the Lakota, who followed great herds of buffalo across the U.S. Midwest, also timed their movements to the motions of the sun and stars.

The ancient traditions that accompanied their migrations are still alive, and in some cases thriving, on the Rosebud reservation today. “We still have the elders that know about this,” Douville says. “And when they die out, we still have the language.” Follow Nadia Drake on Twitter . Comment on This Story Autumnal Equinox 2014: Facts About the First Day of Fall Autumnal Equinox 2014: Facts About the First Day of Fall The sun's position in the sky dictates the equinoxes and solstices. View Images Pack ice forms along a barrier island outside Kaktovik, in the Arctic region of Alaska. Photograph by Sylvain Cordier, Corbis Say goodbye to summer: The Northern Hemisphere's autumnal equinox—the first day of fall—occurs Monday, September 22. Related Content This Week’s Night Sky: See the Red Planet for Yourself With its brilliant colors and crisper days, autumn is a favorite season for many. But what actually happens to make the seasons change?

( See National Geographic's pictures of fall .) The answer is the "clearly definable" position of the sun on the summer and winter solstices, the late Judith Young , a professor of astronomy at the University of Massachusetts in Amherst, told National Geographic News in 2011. "The solstices are very accurately measured as the northernmost point that the sun rises along the horizon in June and the southernmost point along the horizon in December," she said. (See pictures of the sun's path across the sky —an entire year in a single frame.) In modern times, the solstice points became the astronomical definitions of when the summer and winter seasons begin. In the Northern Hemisphere, June features the summer solstice, while in the Southern Hemisphere, June marks the first day of winter. (See " Summer Solstice Pictures: From Stonehenge to Carhenge .") Since the equinoxes fall roughly halfway between the solstices, they got pegged as the starts of the other two seasons, fall and spring, Young said.

Arctic Ice Driven by the Seasons The natural march of the seasons—winter, spring, summer, and fall—are intricately tied to other natural processes, like the melting and freezing of Arctic sea ice. If you were standing at the North Pole on the autumnal equinox, for instance, you could see the sun skim across the horizon, signaling the start of six months of darkness. The careful observer would also note that Arctic sea ice has once again begun to form. (Also see " Shrinking Arctic Ice Prompts Drastic Change in National Geographic Atlas .") "Once you run out of sun, you run out of energy and there is not much the system can do. You are going to start freezing up," said Mark Serreze , the director of the National Snow and Ice Data Center in Boulder, Colorado. The minimum extent of Arctic sea ice is on a long-term decline, a trend caused in part by rising global greenhouse gases that's being closely tracked by scientists. Lag of the Seasons Defining the start of the seasons based on the sun's positions may seem counterintuitive. After all, in the summer, daylight begins to grow shorter just as the season officially begins.

Shouldn't the June solstice instead be called midsummer, as was celebrated in Shakespearean times? From a climatological perspective, the answer is no, according to Young. She explained that "there's something called the lag of the seasons where [for example] the temperatures continue to warm up after you've had the northernmost sunrise in the Northern Hemisphere" on the summer solstice. (Also see " Why Do Fall Leaves Change Color? ") This lag means that, in the Northern Hemisphere, the warmest days of summer don't actually arrive until late July and early August, and the coldest days of the winter are in January and February. For the same reason, though the peak of solar radiation in the Arctic occurs on the Northern Hemisphere's summer solstice, the maximum melt rate always occurs in July, "because it takes a while for the melt to get going," Serreze said. The melt rate starts to slow in August as the sun gets lower in the sky. The sea ice minimum usually occurs around September 13, which is a few days before the start of fall.

This regularity allowed for the construction of Stonehenge in England some 5,000 years ago, where sunrise on the summer solstice is still celebrated with fervor. Autumnal Equinox Illusions But don't be fooled by the notion that on the autumnal equinox the length of day is exactly equal to the length of night. The true days of day-night equality always fall after the autumnal equinox and before the vernal equinox, Geoff Chester, a public affairs specialist with the U.S. Naval Observatory in Washington, D.C., explained to National Geographic News in 2005. The difference is a matter of geometry, atmosphere, and language. Day and night would each be exactly 12 hours long on a spring or fall equinox only if the sun were a single point of light and Earth had no atmosphere. But the sun, as seen from Earth, is nearly as large as a little fingertip held at arm's length—a size known to astronomers as half a degree wide. Sunrise is defined as the moment the top edge of the sun appears to peek over the horizon. Sunset is when the very last bit of the sun appears to dip below the horizon.

(See pictures of fall colors .) The vernal and autumnal equinoxes, meanwhile, occur when the center of the sun's disk crosses what's known as the celestial equator, an imaginary line that projects outward from Earth's Equator, Chester noted. What's more, Earth's atmosphere bends sunlight when it's close to the horizon, making the sun appear to rise a few minutes earlier than it actually does. "Those factors all combine to make the day of the equinox not the day when we have 12 hours [each] of light and darkness," Chester said. Blocked Views Most people will never see the full 12 hours of sunup and sundown on the autumnal equinox, the University of Massachusetts' Young noted in 2010. That's because most people have hills or trees blocking their views of a flat horizon. Thus, they see the sun rise later and set earlier than it does when the horizon has no obstruction, she said. What's more, for people who don't live on the Equator, the sun still rises and sets at an angle to the horizon, noted Young, who built a Stonehenge-like solar calendar and observatory on the University of Massachusetts campus.

Even though the sun rises due east and sets due west on the autumnal equinox, "you'll only see an east sun rising and west sun setting with an obstruction-free horizon," she said. Warming Arctic Up in the Arctic, the season of darkness is under way, but there's still more warmth now than in past decades, noted Serreze. That's because the loss of sea ice over the years has exposed more of the ocean, which absorbs the sun's heat. The heat gets released back to the atmosphere as fall sets in. "We see much warmer conditions in the Arctic than we used to see, and that is really in part because the ocean is moving all of this energy back upward into the atmosphere and into space," he explained. Follow John Roach on Twitter . Comment on This Story Vernal Equinox 2016: 5 weird traditions to celebrate the first day of Spring - Mirror Online News Vernal Equinox 2016: 5 weird traditions to celebrate the first day of Spring Yesterday marked the first day of Spring. Here's everything you need to know about the Vernal Equinox 2016 Share Get daily updates directly to your inbox + Subscribe Thank you for subscribing!

Could not subscribe, try again laterInvalid Email Spring is in the air, and this weekend saw the Vernal Equinox - which traditionally marks the beginning of the Spring season in the Northern Hemisphere. If you live in the UK, that hopefully means the daffodils are blooming, blossom is on the trees, Easter is coming, and lambing season is well underway. Here's everything you need to know about the first day of spring . Why does the Vernal Equinox happen? The equinox occurs because of the tilt of the Earth in relation to the Sun. This is what causes the seasons. The Earth's tilt is 23.5 degrees relative to the plane of its orbit and means that, although one revolution of the planet takes 24 hours, it's different depending on the time of year. During the summer time, the Northern Hemisphere is tilted towards the Sun, so we get longer days as more light falls on this part of the planet. In the winter time it's the Southern Hemisphere that gets the majority of the light. "Equal night" On the spring equinox, the Earth hits the turning point in its orbit where neither the North or the South poles are tilted towards the sun.

As a result, the Sun spends a roughly equal amount of time above and below the horizon at every location on the Earth, so night and day are about the same length. The word equinox is Latin for "equal night". Meteorologists use it as the official turning point in the seasons because - although it can vary from year to year, it allows for the most accurate record-keeping. (Photo: Getty) When is the spring equinox? This year, the vernal (or spring) equinox takes place on Sunday March 20. After this point, the days will get longer and the nights will get shorter until the summer solstice on June 20, when the pattern will reverse. How is the spring equinox celebrated? Equinoxes and solstices mark key stages in the astronomical cycle of the Earth. The March equinox has long been celebrated as a time of rebirth in the Northern Hemisphere. (Photo: Getty) Many cultures celebrate spring festivals and holidays around the March equinox, like Easter and Passover. However, there are also a few more unorthodox celebrations - some of which date back thousands of years.

If you're looking for a way to mark the occasion, here are five weird traditions to give you inspiration: 1. Balance an egg (Photo: Getty) There is an ancient Chinese belief that you can stand an egg on its end on the first day of spring. The theory goes that, due to the sun's equidistant position between the poles of the earth at the time of the equinox, special gravitational forces apply. This is, of course, nonsense. But it does still make for a fun party game - and you can save your eggs to paint on Easter Day. 2. Throw some coloured powder (Photo: Raj K Raj/Hindustan Times via Getty Images) Holi is an ancient Hindu festival celebrating the victory of good over evil. It takes place each year around the time of the vernal equinox. Known as the "festival of colours", it is celebrated by tossing vibrant coloured powders onto each other and dancing in the streets. This year, Holi falls on Wednesday March 23, but if you fancy brightening up your Sunday, why not get started a little early? 3.

Wear a shamrock The symbolic plant of the equinox in Druidry is the trefoil or shamrock, which is also customarily worn on St. Patrick's Day. The three leaves shaped like hearts were associated with the Triple Goddess of Celtic mythology, otherwise known as the "Three Morgans" The shamrock is thought to be symbolic of the regenerative powers of nature. 4. Plant seeds The spring equinox is symbolic of rebirth, renewal, and growth, and in ancient Italy, it was traditional for women to plant seeds in the gardens of Adonis on this day. The custom persists in Sicily, where women plant seeds of grains - lentils, fennel, lettuce or flowers - in baskets and pots. When they sprout, the stalks are tied with red ribbons and the flowers are placed on graves on Good Friday, symbolising the triumph of life over death. 5. Visit an ancient monument (Photo: PA) Many of the world's ancient monuments were built as astrological calendars, to map the movement of the Sun over the course of the year. The equinox is therefore a great time to visit these monuments, as they are often aligned to make the most of the Sun's unique position in the sky.

At Stonehenge in Wiltshire, the sun can be seen rising precisely between two stones, while at Chichén Itzá in Mexico, the rising sun transforms one edge of the giant pyramid into a blazing serpent, representing the Mayan god Kukulcan. Read more: When do the clocks go forward in 2016? Update US search giant Google has marked the vernal equinox and the first day of Spring with one of its famous doodles . The animated illustration shows pink cherry blossom growing on a tree surrounded by boulders. A series of cartoon eyes then appear in the boulders, gazing in wonder, until one sneezes and blows aways the blossom. Video Loading Equinox Explained: Why Earth's Seasons Will Change on Sunday Equinox Explained: Why Earth's Seasons Will Change on Sunday By Geoff Gaherty, Starry Night Education | September 18, 2013 04:11pm ET MORE The sun crosses the celestial equator on September 22 at 4:44 p.m. EDT. On this date the sun rises due east and sets due west, and the day and night are of equal length.

Credit: Starry Night Software The seasons will change this Sunday (Sept. 22), with the Northern Hemisphere moving into autumn and the South emerging from winter into spring. The celestial event that marks this transition is called an "equinox," and it happens twice every year, around March 21 and Sept. 21. Just what is an equinox, and why does it occur? The Earth moves in two different ways. First, the planet spins on its polar axis — a line through the north and south poles — once every 24 hours, causing the alternation of day and night. Secondly, it moves in its orbit around the sun once every 365.25 days, causing the annual cycle of seasons. The equinox occurs when these two motions intersect. [ Season to Season: Earth's Equinoxes & Solstices (Infographic) ] Because the Earth is so big, its mass has an enormously powerful gyroscopic effect. For this reason, its poles always point in the same direction, although a major earthquake can cause tiny wobbles in this axis. Most importantly, the Earth's motion around the sun has absolutely no effect on the direction the poles are pointing, which has very important consequences for Earth's seasons .

Astronomers mark the positions of objects in the sky relative to the Earth's poles of rotation (those are the red lines you see in the picture). The most important line is the celestial equator, which divides the sky into the Northern and Southern Hemispheres. The Earth's pole of rotation is tilted 23.4 degrees relative to the plane of its orbit. This tilt is always toward the same point in the sky, called the celestial pole, no matter where in its orbit around the sun the Earth happens to be. This tilt makes it appear to observers on Earth's surface that the sun is moving across the sky at an angle to the celestial equator. This is marked by the green line in the image, called the "ecliptic" because eclipses happen along this line. Twice a year, the sun crosses the celestial equator, moving from the Northern Hemisphere to the Southern Hemisphere, or vice versa. These two crossings are very important for the inhabitants of Earth, because they mark the change in the direction the sun's rays fall on Earth. Specifically, on Sunday, the sun will move from the Northern Hemisphere to the Southern Hemisphere.

It will pass overhead everywhere along the Earth's equator on that date, and the sun will rise exactly in the east and set exactly in the west. Day and night will also be of roughly equal length. ("Equinox" is derived from the Latin for "equal night.") After Sunday, the sun will shine more on the southern half of our planet and less on the northern half. Summer will be over in the Northern Hemisphere, and fall will have arrived. Winter will be over in the south, and spring will begin. The sun will continue on its path southward for the next three months, reaching its southernmost point on Dec. 21, the date of the "solstice." In the Northern Hemisphere, the days will become shorter, the nights longer, and the temperatures colder during this three-month trek, all as a result of the sun's being south of the celestial equator. It's always important to remember that this is part of a cycle, and that after Dec. 21 the sun will start moving northward again, and spring will be on its way. This article was provided to SPACE.com by Starry Night Education , the leader in space science curriculum solutions. Follow Starry Night on Twitter @StarryNightEdu .

Equinox & Solstice Celebrations | Earth Wisdom | Earth Nursery Equinox & Solstice Celebrations Long before the dawn of any of the modern day way of life, numerous cultures followed a more simplistic path. Guided by the natural cycle of birth-life-death-and-renewal, the ancients marked their seasons by celebrating each phase of the wheel of life. Both male and female principals were honored, God and Goddess, and each was given honor as the sun and moon entwined in their cosmic dance. The festivals that mark the change of season—winter, spring, summer and fall—have been transposed to our modern world. These celebrations explore their meanings of these sacred celebrations, incorporating their meaning into the needs of our world today. We celebrate the 'quarters' on the 21st to connect with the 'Peace the 21st' Celebrations that are taking place in hundreds of cities all over the world. Celebrations Dates: Fall Equinox Hidden Mysteries - Find Your Inner Inspiration Now Fall Equinox Hidden Mysteries Find Your Inner Inspiration Now Fall or Autumn Equinox is September 22 in 2012.

Fall is the 4th and final major Sun Cycle of the year and it means a time of changing Focus and direction in your life. From the Equinox, your consciousness moves slowly inward as the nights lengthen and the days shorten. Follow your natural inclination to turn inward and you'll find the wisdom, riches and inspiration for your next cycle (year) ahead. The chaotic times of summer and rapid growth means lots of changes - some loss and some gain. What's next? Fall is the time of harvesting, and also the time to take stock of what you harvest. The Autumn Earth Mother is celebrated around the world. First for her bountiful harvest and then, second, as the guide to turn inward, exactly as She does, withdrawing from the surface, during the coming winter season. If your returns this season are not what you hoped, now is the time to reflect, find your balance and look for what within you must change to assure greater success in the coming year. This is the ending of the annual Sun cycle and for many, November 1st marks the beginning of a New Year. For others, Winter Solstice marks new year's beginnings, with New Year on January 1st designated as the day of change to the new.

Here are the traditions and history that lie within your genetic coding. Autumn actually begins August 1st and ends October 31st - with the Fall Equinox marking the mid-point. (Western calendars term the "Equinox" the first day of Autumn perhaps because they are no longer aware of the connection between nature, harvesting and Solar cycles.) The amazing beauty of Autumn lights up the Fall days. The leaves soon fall and the trees withdraw inward - a reminder that winter is coming and a time for reflection is near. For our agrarian ancestors, Fall Equinox (and longer - often through October) were the last harvests of the year. At the end of the time of gathering in, storing, and preparing for the coming Winter, the villagers had time --and good reason-- to celebrate plentiful foods, to feast and to dance. The Fall Equinox (September 21-23) is the 3 day period when the sun appears to stand still. Think of it as a time to find your balance as the seasons change and as your Focus or perception changes.

"Yesterday I was clever so I wanted to change the world and today I am wise so I am changing myself." Zahid Iqbal Khan Now is a time to reflect between your past and your future. You are standing on a threshold between what was, and what will be. Look back at all you've accomplished, and look forward at the new adventures to come. If nothing WITHIN you CHANGES, then your past will be your future. Fall Equinox is a traditional time of gratitude and thanksgiving around the world. Join in the flow of the times and add your appreciation for all you've experienced and received this past year - and your Joyful expectations for the coming year. You are setting your own future in motion now with a potent surge of energy during the transition point. From these days forward, the night's lengthen and the days shorten. All of life turns within. You are moving from your more "Yang" masculine, action oriented self, into the realms of the inner-world, the "Yin" and your feminine, intuitive, receptive, creative self. This inward journey culminates on Winter Solstice, and ends at Spring Equinox as the energy again turns, this time from within, to move out again into the world.

Autumn Abundance and the Harvest Moon "Autumn" is a derivative of the Latin "autumnus" referring to harvesting. Equinox literally means "equal night." Day and night are each 12 hours, and the sun rises in true east and sets in true west. The Sun appears to "stand still" and finds balance before continuing. After the Equinox you view the most rapid change in the Sun's apparent motion. "Everyone must take time to sit and watch the leaves turn." Elizabeth Lawrence The warm brilliant colors bely the cold barren days ahead. All of Nature gives thanks for the year past and looks inward toward the year to come. As the nights lengthen and cool, the trees change into their Fall colors. Fruits, vegetables and grains for Winter are harvested now. Hunting season also starts in the Fall and wild game was a staple of life. Fall is also when farmers slaughtered farm animals and preserved meat for the long winters. The abundant harvest is symbolized by the horn of plenty or the cornucopia overflowing with Fall bounty and huge feasts, music and dancing. In 2010 the Fall Equinox is 11 pm PDT on September 22nd.

The full moon closest to the Equinox is know as the Harvest Moon, in 2010 it is on the following day, September 23rd. The full moon lit up the fields so the farmers could work late into the night harvesting. If the full moon closest to the Autumnal Equinox is in October, then the September moon is typically named the Corn Moon. Science Facts: How the Fall Equinox and Seasons change. The Fall Equinox, in the Northern Hemisphere, is the point at which the Sun appears to cross the celestial equator from north to south. In the Southern Hemisphere, the opposite is seen, and there it is the time of the Spring Equinox. All life is conceived as a duality, and here the two opposites exist visibly - with the Equinoxes as the transition points. The planets are spinning and orbiting - hardly noticed day to day. changes evolve slowly and if you pay attention - do not catch you off guard or in turmoil.

The equinoxes are points moving in a westward direction known as the "precession of the equinoxes" (first noted by Hipparchus about 120 B.C and "rediscovered" in Western Science in 1680's by Sir Isaac Newton). It takes 25,800 years for the equinoxes to pass through all the constellations of the zodiac. That time period is noted historically in the Vedic and Mayan texts as prophesizing great worldwide changes...Like the Age of Aquarius. Fall Equinox in story and myth. Stories and myth are the histories of a culture - some from religious texts and some from verbal traditions. The truths, wisdom and teachings of the time are embedded within parables, songs and dances -- and within your genetic code. Fall is a time of huge changes, and changes are always a time of great joy and great sorrow. For everything new replaces something old. There is joy in the harvest and the sadness of endings or "death" of the old year.

With the harvesting of fruits, nuts, squash and melons is the reminder that within the harvest (and the death of the plants) -- within the fruit, are the seeds of new life and a promise for the coming year. There is also the realization that the Wheel of the Solar Seasons has turned, cycling through another year once again. The Fall Harvest holds the promise for the coming year. Deep within the fruits, nuts, berries and vegetables are the seeds of the future. The same is true for you - as you assess your harvest, look for the seeds of new beginnings. Your time is circular not linear, there is no end without new beginnings, and no new beginnings that will not end. It is the Flow of Good Fortune to an ever-expanding future, and the flow of life eternal. Finding balance in the changes Holidays are a time to align yourself with the forces of Nature. The Fall Equinox is a powerful doorway and opportunity to restore your balance and to bring harmony to key life projects and relationships. "Autumn is a second leaf is a flower." Albert Camus Is your life in balance? Has your own personal harvest been good? What new life experiences brought you opportunities?

You only learn from experience, and only gain wisdom from self-reflection and awareness of the whole story of your journey. It is in the quiet and inward-time of Winter that your Wisdom will surface as your Inspiration. Your wisdom then becomes a part of who you are. Gather together your experiences and prepare to go on an inward spiraling journey. Stories and Myths of the inward journey All of these wisdom teachings tell of the same inward journey, and all are around the Fall Equinox. They are from different cultures and times and yet speak of the same cycle. The high surf of summer crests and soon calm prevails A time of quiet is fast approaching - and longer nights too. The Greek Goddess Persephone In Greek mythology, Persephone (Kore or Cora) was the embodiment of Mother Earth's fertility - and at the same time - she was the Queen of the Underworld. The story: Persephone, the daughter of Earth Mother Demeter, is abducted and becomes the wife of Hades who governs the underworld. In Demeter's anguished seeking her daughter, she withdrew from the earth (hence winter and the withering of the crops) until Zeus ordered Hades to return Persephone.

Hades tricked her into eating pomegranate seeds, which compels her to return to the underworld for a season each year. Her myth explains the natural processes, with the descent and return of the goddess bringing about the change of seasons. But there's more to the story. Mystical Insights. Persephone is a Greek life-death-rebirth deity or "resurrection" deity. She is a God who is born, suffers a death-like experience, passes a time in the underworld, and is then reborn. (Male examples are Osiris, Baldr, Dionysus, and Odin.) Persephone is the central figure of the Eleusinian Mysteries, whose cult dates to 1700 BC as the "unnamed goddess" worshiped in Crete. The name of "Persephone" is never spoken for she was also the feared Queen of the Dead. She was simply referred to as "Kore" or "the Maiden." The Winter months (soon to come) are a time of "going into the inner or underworld" and there reigning as the all powerful ruler. The mystery schools used the seasons as imputes for change and personal growth.

The symbolic message is a time to move from the outer to the inner realms - as Diety. Like a god, you set your life in motion from your inner world - and what you imagine, dream and speak - comes to pass. When Demeter and her daughter were united in the Spring the Earth flourished with vegetation and color, but for some months each year, when Persephone returned as Queen of the Underworld, the earth once again became barren. Those that stay on the surface of life at Wintertime, find their future barren too. The rainbow is the promise of good things to come. Victory is assured when your life is designed and then the plan implemented that produces success. Vedic or Hindu Goddess: & Fall Durga Puja. The story: When chaos reigned in the Universe, the Gods called on the Mother of the Universe to save them. In the form of Durga, Mother Kali slew the evil demons - and then peace reigned. Durga is a beautiful warrior Goddess, riding a raging tiger, brandishing twelve weapons in her twelve hands. She is a symbol of the feminine power of protection and victory. Durga, Elusive Victory, represents victory over the domineering mind.

Mystical wisdom teachings. The evil demons are the evils of an uncontrolled mind (mind-blindness, fear, greed, lust and ignorance) that create and attract (via Karma) the chaos you experience in life. The weapons in each of her 12 hands represent an attribute to use to control the mind-maya. She is a reminder that this is the time of year to turn inward, use the feminine power of reflection, the 12 "weapons" she offers, and reign in your wayward mind. It is a time to find your own truth and wisdom and prepare for a victorious coming year. A Durga Puja (purification) is a time for people to show their gratitude to Mother Nature, in the form of the Goddess Durga, for their good fortune.

It is a period to restore and find balance after the long monsoon period of rains (often followed by deadly epidemics.) For many, the religious ceremony is observed on the seventh, eighth and ninth day of the New Moon usually in the month of Ashwin (September to October depending on a lunar calendar.) The Durga Puja is then often followed by the worship of Goddess Lakshmi, the Goddess of Grace, Beauty and Prosperity on the evening of the full moon. Lakshmi is the promise of the abundance to come in the new year -- assuming that you have purged your mind of self-delusion! The Celtic or Wiccan story of Mabon Mabon is a time of change, when we are between the worlds of life (Summer and Autumn) and death (Winter), of light and dark of the day and night --in perfect balance- for one day. The story: Mabon is named after the Welsh God, the "Great Son" or "Great hunter." He is the son of Modron the great Mother Earth, and is the Divine Youth, or Son of Light. Mabon vanishes when he is three days old. His whereabouts are a mystery.

Mabon is finally set free at Yule (Winter Solstice) through following the wisdom of the ancient animals (Blackbird, Stag, Owl, Eagle, and Salmon). The teaching was seldom revealed until a person, through reflection on the animals, discovered the answer themselves. The Inner Mystery Mabon had returned to his Earth Mother's womb or the "Otherworld." In Winter, the earth nurtures the new seeds, or Mabon, and over time the seed gathers the strength to become the new harvest the following year. He has brought light into Mother Earth, and remains until he has enough wisdom and strength and is powerful enough to take over darkness once again. In the story, the "Otherworld" is a challenging place. Here Mabon learns the secrets of cultivation. Within the quiet of nature in the Winter months, a person is renewed and regenerated in the same way. It is a place of new life emerging from the darkness. In the Spring, he is reborn, the source of Light and Joy to His Earth Mother. The Wise animals teach that Fall, the time of Mabon, is a time for quiet, tranquil resting periods.

Without the fallow periods we could not assimilate our experiences and balance our outer consciousness and inner knowing. From our insights, we then weave all that we discover into our coming year. Just as fields need to lay dormant to support new growth -- so do we. The Goddesses associated with Mabon are Morgan, Modron, Persephone, and Epona. Some of the Gods are Thoth, Hermes and Thor. The Corn Maiden (Changing Woman) is a Native American Tradition Many Southwestern tribes rely on corn as their primary food. There are many celebrations in honor of Mother Nature and the Goddess of the Corn, of planting and harvesting. One such tradition combines two stories. A young maiden, as her rite of passage, is honored and celebrated, as she changes from a child, into a woman and potential mother. Special foods, bathing, corn pollen and songs and ceremonies accompany the 2-3 day ritual. At the end, the young woman runs from one end of a long line of well wishers, to the other and then returns.

The Wisdom teaching As she runs they shower her with corn pollen - and she transforms, within the Mystery of Earth Mother's grace, from the girl-child, to the young woman, to the mother, to the elder woman and finally into a wise woman -- at the end of the line of family and friends. The tunnel of tribal members represent the going within time. Now she turns, having experienced her life's journey in a brief moment, and runs back again, changing through the life cycles, and returning to the young maiden. It is turning within to Earth Mother that changes are understood and woven into the patterns of life. From experience and introspection, we gather great strength and then have the personal power to "dance our dream awake." Fall Equinox still reveals vibrant colors and warm days. The grass soon turns brown and withdraws and the sun's power to warm lessons and life cools down.

Worldwide Fall Equinox Traditions The Fall Equinox is also known as the first day of autumn: Harvest Home, Harvest Tide, Mabon, Alban Elfed, Autumn Equinox, Autumnal Equinox, Cornucopia, Feast of Avilon, Festival of Dionysus, Night of the Hunter, Second Harvest Festival, Wine Harvest, and Witch's Thanksgiving. The first cusp of Libra was the Fall Equinox term used by navigators and astrologers. It is the turning point, astrologically, from Virgo to Libra, symbolized by the scales, for balance. This Fall Equinox day of transition shows up on pagan, Mayan, American Indian, ancient Irish and Druid calendars. "It was Indian summer, Seasons Calculator – Seattle, USA - Washington years 2012–2022 Dec 21 1:48 pm PST * All times are local time for Seattle. Dates are based on the Gregorian calendar . Times adjusted for DST if applicable. Current year is highlighted. The Seasons Calculator shows the times and dates of Vernal (Spring) & Autumnal (Fall) equinoxes and Summer and Winter solstices all over the world. Advertising

Question: Yesterday marked the first day of fall. Was it a solstice? Or an equinox?
Answer: Equinox